Grinding burr



' June 9, 1925.Y l I 1,541,488"

5.1M@ ELY GRINDING' BURR FiledvJune 25, 1924 2 Shets-Sheat' 1 17a/@72az' Patented June 9, 1925.

UNITED STATES PATENT: OFFICE.

BERNARD M. ELY, 0F MARSHALL, MICHIGAN, ASSIGNOR TO LAMBERT MACHINE CO'M-IANY, OF MARSHALL, MICHIGAN, A CORPORATION OF MICHIGAN.

GRINDING v:BUR-It.

Application led .Tune 25, 1924. Serial No. 722,286.

To all whomy it may concern Be it known that I, BERNARD M. ELY, acitizen of the United States, residingV vat Marshall, in the county ofCalhoun and State of Michigan, have invented useful Improvement inGrinding Burrs, of which the following is a specification.

This invention relates to improvements in grinding burrs and is hereshown as embodied in a device especially adapted for the reduction ofroasted coffee berries, previously broken. The grinding burrs areadapted to reduce such broken coffee berries into various uniform gradesof tineness as may be desired.

By the use of my invention, the broken coffee berries are cut ratherthan crushed. By the use of my invention, it is possible to produce veryfine, steel cut, coffee of a uniform grade.

Although the invention is here. shown as embodied in a device especiallyadapted for grinding coffee which has been previously broken to acertain extent, it is evident that, without det-racting from the spiritof the invention, the same may be used for grinding or cutting wholecoffee berries, and may be used for cutting or grinding other cerealsand substances.

In that form of device embodying ,the features of my invention shown inthe accompanying drawings, Figure 1 is a view in vertical cross section,Fig. 2 is a view as indicated by the line 2-2 of Fig. 1, Fig. 3 is aview taken as indicated by the line 3-3 of Fig. 1, Fig. 11 is a view onan enlarged scale of a portion of the peripheral surface of the runnerburr showing the teeth thereon, and Fig. 5 is a view taken as indicatedby the line 5-5 of Fig. 4.

As shown in the drawings, 10 indicates a suitable hopper in which thecoffee orl other material to beground is fed in any suitable manner. Inthe event that coffee is to be ground, the berries are preferably brokento a certain extent before being 11 indicates a substantially cy-ilindrical housing in which the grinding burrs are suitably mounted. 12indicates a stationary burr which is supported in the housing 11. Thisburr will be seen most clearly in Fig. 8. It is to be noted that it isfirmly attached to the circular web 13 in the housing 11 by means of thescrews 14.

ground.

a new and as indicated by Tvhe burr 12 is provided with a central recess15 through which the coffee is fed from the passageway 16.

Centrally arranged within the cylindrical i v,hopper 10, being directedthereto by the each other in order to `vary the grade of c iineness towhich the material is to be cut. This adjustment, in the device hereshown. is accomplished in the followingmanner.l The shaft 17 is extendedbeyond the disk 18 as indicated by 17. The end 17a ofthe I shaft issupported by suitable ball bear'-A ings 20 in a cylindrical member 21mounted within the cylindrical casing 11. Mounted on the end of thecasing 11 is a cover 22 held in place by means of the thumb sc-ren1 23.The cover 22 supports a sleeve 2-1 adapted to be rotatedv by the handwheel 25. The inner end of the sleeve 24 as indicated by 24C2L isprovided with internal threads engaging external threads on the centralpart of the member 21. The member 21 is prevented from rotating by meansof the pin 26 but this pin permits it to slide inwardly and outwardly inthe casing 11. By this construction, rotation of the hand wheel 25serves to draw the member 21 inwardly or outwardly. This movement beingtransmitted through the bearings 20 also pulls the shaft 17 carrying thedisk 18 and ruimer burr 19 inwardly orl outwardly thus moving the runnerburr 19 i 'closer to or farther away from the sta- The other end of theshaft 17b is squared in order to permit its engagement by a squarecollarl (not shown) so that it may be rotated and still permit theadjustmentof the disks above referred to.

I will now describe more in det-ail the particular construction of theburrs themselves. The runner burr (best shown in Figs. 2, i and 5) isprovided at its periphery with four concentric circular rows of teeth.Each tooth .is prismatic in shape.

tionary burr 12.

with its ends beveled. In Fig. 4 one of these teeth is .indicated by thereference numeral 30, the beveled ends being indicated by 30a. The outerrow of teeth is uninterrupted. Each of the second and third rows fromthe periphery, however, has each alternate tooth removed, thus leavingbetween each two teeth a flat or plain surface 31 having an areasubstantially the same as the area of the base of a tooth. The fourthrow from the periphery also has alternate teeth removed but instead ofleave ing a flat or plain surface between each two teeth, there isformed a groove 32 which eX- tends inwardly as indicated by 32?L beyondthe inner row of teeth. The bottoms of the grooves 32 at their innerends as indicated by 32" terminate flush with the surface of the burritself. It is to be noted that the face of the burr inside of the rowsof teeth, as indicated by 33, is depressed or sunken below the bases ofthe teeth 30. The bottoms of the grooves 32 have their outer endssubstantially flush or on a level with the bases of the teeth 3() andtheir inner ends on a level with the central face 33 of the burr. Thisconstruction is most clearly shown in Figs. 4 and 5. The teeth in thesecond, third and fourth rows (counting from the periphery) are instaggered. relation. The stationary burr is provided with teeth formedsimilar to those on the runner burr. The rows of teeth on the runnerburr are slightly smaller than the corresponding rows of teeth on thestationary burr so that the rows of teeth on the two burrs willinterlock when the burrs are in grinding relation. That is, the outerrow of teeth on the runner burr lies between the outer row and thesecond row on the stationary burr. rlhe second row from the outside onthe runner burr lies between the second and third rows from the outsideon the stationary burr, and so on. If desired, the rows of teeth couldbe formed to interlock in another way by havingthe rows on ruimer burrcorrespondingly larger than those on the stationary burr. It is to benoted that adjacent teeth in different rows do not lie on radial linesbut slant somewhat toward the tangent. In other words, a line drawnthrough adjacent teeth, in the different rows (such as the section linewill form an angle with a radial line.

In Fig. l the direction of rotation of the burr is sho-wn by Jthe arrow,and it will be noted that a line drawn through adjacent teeth in thediiiierent circular rows slans away from a radius toward the directionoi rotation as such line is projected inwardly from the periphery of theburr. ne grooves 32 likewise are extended inwardly in line with adjacentteeth in the different rows. The runner burr 19 also carries eightcircular feeders or battles 35 forming pockets therebetween. The innerends ol the feeders 35, as indicated by 35, terminate some distance fromthe shaft 17. Iiying over the feeders 35 is a circular plate 36 held inplace by means of the screws 37. The outer edge of the plate 36 liesjust inside ol the inner row of teeth. The inner edge of the plate 36,as indicated. by 33, lies just outside of the inner ends 35 of thefeeders 35; In other words, the feeders 35 are virtually thin curvedpartitions lying between the face 33 of the burr and the plate 3G, thusforming Vpockets therebetween. Each of the fee-ders 35 is curvedbackwardly toward the direction of rotation from its inner end to itsouter end, so that upon Vrotation of the inria?, such feeders will tendio force material in the pockets outwardly to the teeth.

In the operation of the device, material is fed from the hopper l0through the passage 16 thence through the circular opening l5 where itpasses through the opening in the circular plate 3G. The material thenmeets the disl-l; and drops into the pockets between the feeders Theshape of the feeders 35 and rotation of the disk assisted by gravity andcentrifugal force, forces the material outwardly and between the teethof the two burrs. The grooves 3; serve to assist in feeding of materialto the outer rows of teeth. After the material has bee'i ground by theteeth it escapes into the an nular space 33 outside of the dist i8 and`tl'icnce linds an outlet through the opening 39. rEhe disk 13 is alsoprovided with two diametrically arranged wipers 40 to move the materialaround'in the annular space 33 until it finds an exit through theopening 39. f

VVlfhile I have shown and described certain embodiments .of myinvention, it is to be understood that itis capable of manymodifications. Changes, therefore, in the construction and arrangementmay be made `without departing from the spirit and scopo of theinvention as disclosed in the append ed claims, in ywhich itis myintention io claim all novelty inherent in my invention as broadly aspossible in view of the prior art.

lf'Vhat I claim as new and desire to secure by Letters Patent, is:

l. A grinding burr provided at its periphery with concentric rows otteeth, the central portion of the face of the burr inside of the innerrow of said teeth being; flat and depressed below the leyel of the baseYot' said teeth, and a series of inwardly ext-ending grooves in the faceof the burr having their outer ends lying between the teeth of the innerrow, the bottoms of said grooves at their outer ends being substantiallyon a level with theV base of the teeth and at their inner endssubstantially on a level with the lltl lcgepressed central portion ofthe face of the urr.

2. A stationary burr and a runner burr, said burrs having on theirperipheries interlocking concentric rows of teeth, the central portionsof the faces of said burrs inside of said teeth being separated, aplurality of radial baflies or feeders on the runner burr having theirouter ends terminating near Vthe teeth, and a fiat circular plate lyingon top of said baffles or feeders.

3. A stationary burr and a runner burr, said burrs having on theirperipheries interlocking concentric rows of teeth, the central fportions of the faces of said burrs inside of said teeth beingseparated, a plurality of radial baflies or feeders on the runner burrhaving their outer ends terminating near the teeth, and a fiat circularplate lying on top of said baffles or feeders, the outer periphery ofsaid plate lying adjacent the inner row of teeth on the runner burr, andthe inner periphery of said plate lying close tothe inner ends of saidbaffles or feeders.

l. A stationary burr and a runner burr, said burrs having on theirperipheries interlocking concentric rows of teeth, the central portionsof the faces of said burrs inside of said teeth being separated, and aplurality of covered radial pockets on the runner burr having theirouter ends lying adjacent the teeth and their inner ends open.

5. A stationary burr and a runner burr, said burrs having on theirperipheries interlocking concentric rows ofy teeth, the central portionof the face of each burr inside of said teeth being flat and depressedbelow the level of the base of said teeth, a series of inwardlyextending grooves in the face of each burr having their outer ends lyingbetween the teeth of the inner row, the bottoms of said grooves at theirouter ends being substantially on a level with the base of the teeth andat their inner ends substantially on a level with the depressed centralportion of the face of the burr, and a plurality of radial baffles orfeeders on the runner burr having their outer ends terminating near theteeth.

G. A stationary burr and a. runner burr, said burrs having on theirperipheries interlocking concentric rows of teeth, the central portionof the face of each burr inside of said teeth being flat and depressedbelow the level of the base of said teeth, a series lof inwardlyextending grooves in the face of each burr having their outer ends lying1between the teeth of the inner row, the bottoms of said grooves attheir outer ends being substantially on a level with the base of theteeth and at their inner ends substantially on a level with thedepressed central portion of the face of the burr, a plurality of radialbaffles or feeders on the runner burr having their outer endsterminating near the teeth, and a flat circular plate lying on top ofsaid baliies or feeders.

7 A stationary burr and a runner burr, said burrshaving on theirperipheries interlocking concentric rows of teeth, the central portionof the face of each burr inside of said teeth being flat and depressedbelow the level of the base of said teeth, a series of inwardlyextending grooves in the face of each burr having their outer ends lyingbetween the teeth o-f the inner row, the bottoms of said grooves attheir outer ends being substantially on a level with the base of theteeth and at their inner ends substantially on a level with thedepressed central portion of the face of the burr, and a plurality ofradial pockets on the runner burr lying between the depressed centralportions of the faces of the burrs, said pockets being open at theirinner ends and having their outer ends terminating near said teeth.

8. A stationary burr and a runner burr,

said burrs having on their peripheries in-V terlocking concentric rowsof teeth, t-he central portion of the face of each burr inside of theinner row of said teeth being flat and depressed belo-w the level of thebase of said teeth, and a plurality of covered radial pockets on therunner burr lying between the depressed central portions of the faces ofsaid burrs, said pockets having their inner ends open and their outerends terminating near the teeth.

9. A stationary burr and a runner burr, said burrs having on theirperipheries interlocking concentric rows of teeth, the centra-l Aportionof the face of each burr inside of the inner row of said teeth beingflat and depressed below the level of the base of said teeth, and aplurality of radial pockets on the runner burr lying between thedepressed central portions of the faces of said burrs, said pocketsformed by radial baiiies or feeders ron the runner burr with a circularplate lying on top of said baffles or feeders.

l0. A stationary burr and a runner burr, said burrs having on theirperipheries i11- terlocking concentric rows of teeth, the centralportion of the face of each burr inside of the inner row of said teethbeing flat and depressed below the level ofthe base of said teeth, and aplurality of ra- Y dial pockets on the runner burr lying between thedepressed central portions of the faces of said burrs, said pocketsformed by radial bafiies or feeders on the ruimer burr with a circularplate lying on top of said baffles or feeders, said pockets having theirinner ends open and their outer ends terminating nea-r said teeth.

lVitness my hand and seal this 19th day ofV June, A. l). 1924:. vBERNARD M. ELY.. [n s] lll)

